ICData::NumberOfChecks is O(n) so don't call it in loops

runtime/vm/flow_graph_compiler_x64.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/ast_printer.h"
@@ skipping 1447 matching lines @@
   ASSERT(is_optimizing());
 
   __ Comment("EmitTestAndCall");
   const Array& arguments_descriptor = Array::ZoneHandle(
       zone(), ArgumentsDescriptor::New(argument_count, argument_names));
   // Load receiver into RAX.
   __ movq(RAX, Address(RSP, (argument_count - 1) * kWordSize));
   __ LoadObject(R10, arguments_descriptor);
 
   const bool kFirstCheckIsSmi = ic_data.GetReceiverClassIdAt(0) == kSmiCid;
-  const intptr_t kNumChecks = ic_data.NumberOfChecks();
+  const intptr_t num_checks = ic_data.NumberOfChecks();
 
-  ASSERT(!ic_data.IsNull() && (kNumChecks > 0));
+  ASSERT(!ic_data.IsNull() && (num_checks > 0));
 
   Label after_smi_test;
   if (kFirstCheckIsSmi) {
     __ testq(RAX, Immediate(kSmiTagMask));
     // Jump if receiver is not Smi.
-    if (kNumChecks == 1) {
+    if (num_checks == 1) {
       __ j(NOT_ZERO, failed);
     } else {
       __ j(NOT_ZERO, &after_smi_test);
     }
     // Do not use the code from the function, but let the code be patched so
     // that we can record the outgoing edges to other code.
     const Function& function =
         Function::ZoneHandle(zone(), ic_data.GetTargetAt(0));
     GenerateStaticDartCall(deopt_id, token_index,
                            *StubCode::CallStaticFunction_entry(),
                            RawPcDescriptors::kOther, locs, function);
     __ Drop(argument_count, RCX);
-    if (kNumChecks > 1) {
+    if (num_checks > 1) {
       __ jmp(match_found);
     }
   } else {
     // Receiver is Smi, but Smi is not a valid class therefore fail.
     // (Smi class must be first in the list).
     if (!complete) {
       __ testq(RAX, Immediate(kSmiTagMask));
       __ j(ZERO, failed);
     }
   }
   __ Bind(&after_smi_test);
 
-  ASSERT(!ic_data.IsNull() && (kNumChecks > 0));
-  GrowableArray<CidTarget> sorted(kNumChecks);
+  ASSERT(!ic_data.IsNull() && (num_checks > 0));
+  GrowableArray<CidTarget> sorted(num_checks);
   SortICDataByCount(ic_data, &sorted, /* drop_smi = */ true);
 
   const intptr_t kSortedLen = sorted.length();
   // If kSortedLen is 0 then only a Smi check was needed; the Smi check above
   // will fail if there was only one check and receiver is not Smi.
   if (kSortedLen == 0) return;
 
   // Value is not Smi,
   __ LoadClassId(RDI, RAX);
   for (intptr_t i = 0; i < kSortedLen; i++) {
@@ skipping 258 matching lines @@
   __ movups(reg, Address(RSP, 0));
   __ AddImmediate(RSP, Immediate(kFpuRegisterSize));
 }
 
 
 #undef __
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64